My ex-wife is the mother of my kids, so yes. We've been divorced well over 20 years, so whatever angst should have dissipated. But it's unlikely to happen -- I don't frequent FB, and we don't have the same interests.
As far as the ex-girlfriends, probably not. Those flames went out a long ago.
I am happy with whom I have now.
Machka still chats with several people with whom she had relationships before us. It doesn't bother me in the slightest.